The Acadians lived for almost 80 years in Acadia, prior to the British Siege of Port Royal in 1710. After the Conquest, they lived under British rule for the next forty-five years. During the French and Indian War (the North American theatre of the Seven Years' War), British colonial officers suspected they were aiding the French. The British, together with New England legislators and militia, carried out the Great Expulsion of 1755–1764 during and after the war years. They deported approximately 11,500 Acadians from the maritime region. Approximately one-third perished from disease and drowning. Although one historian compared this event to contemporary ethnic cleansing, other historians suggested that the event is comparable with other deportations in history.[10]

Many Acadians migrated to Spanish colonial Luisiana, present day Louisiana state, where they developed what became known as Cajun culture. Others were transported to France.[11] Some of those were settled secondarily to Louisiana by Henri Peyroux de la Coudreniere. Later on, many Acadians returned to the Maritime provinces of Canada, most specifically New Brunswick. Most who returned ended up in New Brunswick because they were barred by the British from resettling their lands and villages in the land that became Nova Scotia. Before the U.S. Revolutionary War, the Crown settled New England Planters then after the war, Loyalists (including nearly 3,000 Black Loyalists - freed slaves) in former Acadian communities and farmland. British policy was to assimilate Acadians with the local populations where they resettled.

During the seventeenth century,[when?] about sixty French families were established in Acadia. They developed friendly relations with the Wabanaki Confederacy (particularly the Mi'kmaq), learning their hunting and fishing techniques. The Acadians lived mainly in the coastal regions of the Bay of Fundy; farming land reclaimed from the sea through diking. Living in a contested borderland region between French Quebec and British territories, the Acadians often became entangled in the conflict between the powers. Over a period of seventy-four years, six wars took place in Acadia and Nova Scotia in which the Confederacy and some Acadians fought to keep the British from taking over the region (See the four French and Indian Wars as well as Father Rale's War and Father Le Loutre's War).

While France lost political control of Acadia in 1710, the Mí'kmaq did not concede land to the British. Along with some Acadians, the Mi'kmaq used military force to resist the founding of British (Protestant) settlements by making numerous raids on Halifax, Dartmouth, Lawrencetown and Lunenburg. During the French and Indian War, the Mi'kmaq assisted the Acadians in resisting the British during the Expulsion of the Acadians.[12][page needed]

The British Conquest of Acadia happened in 1710. Over the next forty-five years the Acadians refused to sign an unconditional oath of allegiance to Britain. During this time period Acadians participated in various militia operations against the British and maintained vital supply lines to the French Fortress of Louisbourg and Fort Beausejour.[13] During the French and Indian War, the British sought to neutralize any military threat Acadians posed and to interrupt the vital supply lines Acadians provided to Louisbourg by deporting Acadians from Acadia.[14][15]

Many Acadians might have signed an unconditional oath to the British monarchy had the circumstances been better, while other Acadians did not sign because they were clearly anti-British. For the Acadians who might have signed an unconditional oath, there were numerous reasons why they did not. The difficulty was partly religious, in that the British monarch was the head of the (Protestant) Church of England. Another significant issue was that an oath might commit male Acadians to fight against France during wartime. A related concern was whether their Mi'kmaq neighbours might perceive this as acknowledging the British claim to Acadia rather than the Mi'kmaq. As a result, signing an unconditional oath might have put Acadian villages in dangers of attack from Mi'kmaq.[16]

In the Great Expulsion (le Grand Dérangement), beginning in August 1755 under Lieutenant Governor Lawrence, approximately 11,500 Acadians (three-quarters of the Acadian population in Nova Scotia) were expelled, their lands and property confiscated, and in some cases their homes burned. The Acadians were deported throughout the British eastern seaboard colonies from New England to Georgia. Although measures were taken during the embarkation of the Acadians to the transport ship, some families became split up. Thousands were transported to France. Most of the Acadians who went to Louisiana were transported there from France on 5 Spanish ships provided by the Spanish Crown to populate their Louisiana colony and provide farmers to supply New Orleans. The Spanish had hired agents to seek out the dispossessed Acadians in Brittany and the effort was kept secret so as not to anger the French King. These new arrivals from France joined the earlier wave expelled from Acadia, creating the Cajun population and culture. The Spanish forced the Acadians they had transported to settle along the Mississippi River, to block British expansion, rather than Western Louisiana where many of them had family and friends and where it was much easier to farm. Rebels among them attacked New Orleans and killed the Spanish governor. The Spanish later sent infantry from other colonies to put down the rebellion and execute the leaders.

A second and smaller expulsion occurred when the British took control of the North Shore of what is now New Brunswick. After the fall of Quebec the British lost interest and many Acadians returned to British North America, settling in coastal villages not occupied by American colonists. A few of these had evaded the British for several years but the brutal winter weather eventually forced them to surrender. Some returnees settled in the region of Fort Sainte-Anne, now Fredericton, but were later displaced by the arrival of the United Empire Loyalists after the American Revolution.

The Acadians today live predominately in the Canadian Maritime provinces, as well as parts of Quebec, Louisiana and Maine. In New Brunswick, Acadians inhabit the northern and eastern shores of New Brunswick, from Miscou Island (French: Île Miscou) Île Lamèque including Caraquet in the center, all the way to Neguac in the southern part, Grande-Anse in the eastern part and Campbellton through to Saint-Quentin in the northern part. Other groups of Acadians can be found in the Magdalen Islands and throughout other parts of Quebec. Many Acadians still live in and around the area of Madawaska, Maine where the Acadians first landed and settled in what is now known as the St. John Valley. There are also Acadians in Prince Edward Island and Nova Scotia such as Chéticamp, Isle Madame, and Clare. East and West Pubnico, located at the end of the province, are the oldest regions still Acadian.

The Acadians settled on the land before the deportation and returned to some of the same exact land after the deportation. Still others can be found in the southern and western regions of New Brunswick, Western Newfoundland and in New England. Many of these latter communities have faced varying degrees of assimilation. For many families in predominantly Anglophone communities, French-language attrition has occurred, particularly in younger generations.

The Acadians who settled in Louisiana after 1764, known as Cajuns, have had a dominant cultural influence in many parishes, particularly in the southwestern area of the state known as Acadiana.

Today Acadians are a vibrant minority, particularly in New Brunswick, Nova Scotia, Louisiana (Cajuns), and northern Maine. Since 1994, Le Congrès Mondial Acadien has united Acadians of the Maritimes, New England, and Louisiana.

August 15, the feast of the Assumption, was adopted as the national feast day of the Acadians at the First Acadian National Convention, held in Memramcook, New Brunswick in 1881. On that day, the Acadians celebrate by having the tintamarre which consists mainly of a big parade where people can dress up with the colours of Acadia and make a lot of noise.

The national anthem of the Acadians is "Ave, maris stella", adopted at Miscouche, Prince Edward Island in 1884. The anthem was revised at the 1992 meeting of the Société Nationale de l'Acadies, where the second, third and fourth verses were changed to French, with the first and last kept in the original Latin.

The Federation des Associations de Familles Acadiennes of New Brunswick and the Société Saint-Thomas d'Aquin of Prince Edward Island has resolved that December 13 each year shall be commemorated as "Acadian Remembrance Day" to commemorate the sinking of the Duke William and the nearly 2000 Acadians deported from Ile-Saint Jean who perished in the North Atlantic from hunger, disease and drowning in 1758.[17] The event has been commemorated annually since 2004 and participants mark the event by wearing a black star.

Today, there are cartoons featuring Acadian characters and an Acadian show named Acadieman.

In 1847, American writer Henry Wadsworth Longfellow published Evangeline, an epic poem loosely based on the events surrounding the 1755 deportation. The poem became an American classic, and contributed to a rebirth of Acadian identity in both Maritime Canada and in Louisiana.

Acadians in the diaspora have adopted other symbols. The flag of Acadians in Louisiana, known as Cajuns, was designed by Thomas J. Arceneaux of the University of Louisiana at Lafayette, and adopted by the Louisiana legislature as the official emblem of the Acadiana region in 1974.[19]

A group of New England Acadians attending Le Congrès Mondial Acadien in Nova Scotia in 2004, endorsed a design for a New England Acadian flag[20] by William Cork, and are advocating for its wider acceptance.

Notable Acadians in the 18th century include Noel Doiron (1684–1758). Noel was one of more than 350 Acadians that perished on the Duke William on December 13, 1758.[21] Noel was described by the Captain of the Duke William as the "father of the whole island", a reference to Noel's place of prominence among the Acadian residents of Isle St. Jean (Prince Edward Island).[22] For his "noble resignation" and self-sacrifice aboard the Duke William, Noel was celebrated in popular print throughout the 19th century in England and America.[23] Noel also is the namesake of the village Noel, Nova Scotia.

^"Canadian census, ethnic data". Archived from the original on 2013-03-18. Retrieved 18 March 2013. A note on interpretation: With regard to census data, rather than going by ethnic identification, some would define an Acadian as a native French-speaking person living in the Maritime provinces of Canada. According to the same 2006 census, the population was 25,400 in New Brunswick; 34,025 in Nova Scotia; 32,950 in Quebec; and 5,665 in PEI(all stats inaccurate as of 2006 census. Numbers are significantly lower than previously stated)). Many French-Canadians in the Maritimes who are Acadians may have listed 'French' as their ethnicity instead of 'Acadian; the numerous single responses for 'Canadian' also does not give an accurate figure for numerous groups.

^Morris, Charles. A Brief Survey of Nova Scotia. The Royal Artillery Regimental Library, Woolwich. Morris provides a description of the Acadians: "The people are tall and well proportioned, they delight much in wearing long hair, they are of dark complexion, in general, and somewhat of the mixture of Indians; but there are some of a light complexion. They retain the language and customs of their neighbours the French, with a mixed affectation of the native Indians, and imitate them in their haunting and wild tones in their merriment; they are naturally full cheer and merry, subtle, speak and promise fair,..."

^Many of the Acadians and Mi'kmaq people were metis. For example, when Shirley put a bounty on the Mi'kmaq people during King Georges War, the Acadians appealed in anxiety to Mascarene because of the "great number of Mulattoes amongst them" (See Bell, Foreign Protestants, p. 405, note 18a).

^Pritchard, James. In Search of Empire - The French in the Americas, 1670-1730. p. 36: "Abbé Pierre Maillard claimed that racial intermixing had proceeded so far by 1753 that in fifty years it would be impossible to distinguish Amerindian from French in Acadia."

^Naomi E. S Griffiths. From Migrant to Acadian, McGill-Queen's University Press. 2005.p. 47. Acadian family names have come from many areas in France. For example, the Maillets are from Paris; the LeBlancs of Normandy; the surname Melanson is from Brittany, and those with the surname Bastarache and Basque came from the Basque Country.